The present invention relates to an ejector pump for establishing a vacuum and, more particularly, to an ejector pump in which compressed air is injected from a nozzle opening into an ejector opening so that air occupying a suction chamber formed between the nozzle opening and the ejector opening may be evacuated to establish a vacuum in the suction chamber and in a system connected to the former.
An ejector pump of the above-specified type according to the prior art is equipped with an electromagnetic valve around its body so that a pilot valve for opening and closing a nozzle opening may be actuated by the electromagnetic valve. As a result, the ejector pump of the prior art has a complicated structure and a large overall size.